TCP/IP overhead on CPU

Hi.
I have an application running TCP/IP, over wifi. I want to know how much is the overhead of TCP/IP on the processor.
1- I heard that the rule of thumb for network is that for each 1 bit per second, 1 hz of CPU is required. is it right?
2- does dragonboard has wifi NIC with TCP offload engine which I can activate it and reduce the overhead of TCP/IP on the CPU?
3- I want to reduce the frequency of CPU, which will affect the performance of TCP/IP. is there any way that I can reduce this effect?

Thanks,

Regarding the CPU overhead I think you will have to measure that whilst your application is running. To mitigate any effect of CPU frequency scaling you will need to interfere with the governor. “performance” would yield best performance but is very wasteful of power so you are betting off looking at other ones. One option is get your application to switch governors on the fly (i.e. force performance governor when it gets a packet and put back a gentler governor when it is idle).